In light of it being WWDC, any Apple Engineers in here that can help? I don't see anything in new APIs

It is not yet released.

This is not answer but I'll add in my experience: I tried adding FocusState to my app earlier today and was not able to get it working the way I wanted. I was using a UUID as a Value instead of a Field enum, and manually setting the @FocusState to anything other than nil was ignored. I then made the FocusState a Bool to test with a single TextField and it worked fine.

I am only able to get this working if it's embedded within a NavigationView, at the topmost level of my application.